Beginner booby traps can be used to set up some fun pranks or to warn you if an intruder is entering your house. Although you shouldn't count on booby traps as any real form of a defense, they can be a fun and creative form of mischief. Now you just have to learn how to make one.

Steps

Method1

Choosing Your Booby Trap

1

Decide what your goal is. Do you want to play a joke? Alert yourself to a possible intruder? Injure the intruder? Scare someone? All of these questions will determine what kind of booby trap you end up making.

2

Plan accordingly. Design your booby trap before you start making it. You want to be very familiar with the construction and location of the booby trap so that you don’t accidentally spring it on yourself.

3

Inform your friends and family. If you’re hoping to prank your friends and family, then obviously disregard this step. However, you don’t want to accidentally surprise or injure an unintended target. Let people know if you’re building a booby trap and show them exactly how to avoid it. Try to ensure that they don’t forget.

Method2

Making a Basic Tripwire Alarm Trap

1

Buy a piece of fishing wire that will cover the length of your doorway. Measure your doorway ahead of time. You’ll want the wire to be able to reach all the way to the top of the door frame.

2

Buy a keychain siren at a home improvement store. This will be your noise-making device that will notify you when someone enters.

3

Attach the body of the siren to the door. Make sure that it is on the inside of the door or the intruder can easily take it off. You can use tape to securely attach the alarm – a keychain alarm is pretty light. [1]

4

Knot the fishing wire around the alarm pin. Make sure it’s around the part that you pull to make a sound, not the keychain part. [2]

5

Screw a small hook into the top of your doorframe. You’ll want to knot the other end of the fishing wire around this hook. That way, when the door opens, the fishing wire will pull on the alarm pin. Make sure that the fishing wire is relatively taught.

If you just want to know if someone entered your room, just place fishing wire in the front of your door without any sound making device. If the wire is disturbed you’ll know someone came in.

6

Put a small piece of tape on your door. This is another way to see if anyone entered your room. It isn't exactly a tripwire, but it will notify you if anyone has been snooping around. Try to stick the piece of tape up high so that the intruder wont notice that it was there.

Method3

Building up a Beginner Entrance Trap

1

Place marbles in front of your door.[3] This can be very dangerous, so think twice before using this step. The marbles will need to be on a hard wood floor, otherwise they are unlikely to make the intruder slip. Try to leave about two dozen marbles.

Remember to think about the way the door opens. If the door is pushed up and you leave the marbles too close to the door, the intruder will just push all the marbles out of the way.

2

Place a bucket of cold water on top of the door. Fill a medium sized bucket with cold water. Now leave the door slightly ajar. Balance the bucket on top of the door using the door itself as the base for the bucket. It should be a delicate balance, but that’s what you want. When the intruder goes to push the door open, the water will fall right on their head.

3

Make a flypaper trap. This is an incredibly annoying and effective booby trap. All you’ll need is string, nails, and flypaper from a home improvement store. Cut five feet of string and tie one end of the string to the doorknob. Now put two nails in the ceiling. Put the first one approximately a foot from the door and the other approximately five feet away. After you've done that, loop your string through the first nail and start attaching flypaper to the rest of the spring. Don’t wrap the flypaper around the string; just stick it on there so that there is plenty of sticky surface area still available. Loosely loop the end of the string around the final nail. When the door opens, the string will be pulled off of this last nail, the flypaper will swing down from the first nail, and stick to the person who opened the door. [4]

Method4

Setting Up Assorted Household Booby Traps

1

Put Saran Wrap over the toilet.[5] This is borderline prank, borderline booby trap. All you need to do is lift up the toilet seat and cover the inside of the toilet with saran wrap. Try to avoid leaving any creases in the saran wrap – you want it to look as see-through as possible.

2

Turn off the hot water. This is something you’ll probably want to do in the moment. If someone you want to prank is going to take a hot shower, you can run over and turn the hot water off. If they get out of the shower to check the hot water, quickly rush to turn it back on again. This will cause them a lot of confusion.

3

Cut a bottle of orange juice in half. Try doing this with a bottle of orange juice that is about half full. Take off the wrapper first, and then cut the bottle about an inch above wherever the juice line is. Make the cut all the way around so that you can sever the top and bottom sections. Now lightly tape the two sides back together with scotch tape. Put the wrapper back on to hide your trap. Leave the juice on the table and it will fall apart as they go to pour themselves some juice. [6]

Tell him that you're working on a huge surprise, and that if he comes in, he'll be sorry. If that doesn't work, then repeatedly put a plastic cup filled with water on top of your door. If he keeps getting wet coming into your room, he'll eventually give up.

How can I protect my privacy if people keep walking in without knocking?

wikiHow Contributor

Set up something that will hurt their feet if they come in (but nothing too bad), such as marbles or Legos. Put them by your door, and when someone comes in without knocking, he/she will be very uncomfortable.

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Tips

Try not to hurt anyone accidentally.

Don’t test the booby trap on yourself. You might injure yourself.

Choose a victim who will take it well. People who are clumsy, easily startled, or sensitive could be upset by a trap, and that's no fun for anyone.

Don't play a prank you wouldn't want to be played on you!

Always remember the location of a dangerous trap (one that would be used as defense against a burglar).

If the trap is for a specific victim, accidentally-on-purpose give them some info. For example, if it's someone who lives with you, pretend to be telling a friend on the phone where you're hiding something that that person likes (but is really where the trap is located). If you try to make the trap tempting, it'll be more likely for it to work.